1. Field of the Invention
The present invention relates to an electrostatic latent image developer.
2. Description of the Related Art
Electrostatic latent image developers include toner particles containing at least a resin and a colorant, and reduction of the deposition amount of toner particles on a recording material such as paper is required due to the requirement of reducing costs, improving image quality and reducing fixation energy, etc.
However, reduction of the deposition amount of toner particles causes a decrease in image density, and therefore the added amount (ratio) of a colorant (pigment) in toner particles should be increased for retaining a proper image density. Accordingly, attempts are being made to increase the concentration of a colorant in toner particles, but when the concentration of a colorant is increased, the colorant is aggregated in toner particles (the secondary particle size is increased), so that it is difficult to uniformly disperse the colorant.
For liquid developers, that is one type of electrostatic latent image developer, various dispersants for adequately dispersing toner particles in an insulating liquid have been devised, and for example, in Japanese Laid-Open Patent Publication No. 07-319222, a block copolymer composed of a monomer containing a pyridine group and an acrylate-based monomer is proposed as such a dispersant. However, this is intended for dispersing toner particles themselves, and is a technique that is completely different from a technique for uniformly dispersing a colorant in toner particles.